A unique case of localized pemphigus vulgaris.

A 47-year-old Japanese male noticed an erosive lesion on his left lower lip margin in February 1995. Treatment with a corticosteroid ointment gave no improvement. In March 1995, he also noticed a keratotic lesion on his left shoulder; the keratotic mass sometimes fell off, resulting in an erosive lesion, which then became keratotic again. Prior to the lesions, no bulla had been formed. When examined in our outpatient clinic after 5 months, the lesion on his shoulder had a keratotic mass measuring 664 mm in diameter with surrounding erythema (Fig. 1). In the last few years, he had not taken any medicine. During disinfection, the keratotic mass fell off, leaving an erosion. Histology of the skin lesion showed an acanthotic and hyperkeratotic epidermis in the peripheral part of the lesion. Clefts and acantholysis were seen in the suprabasal and lower spinous cell layers (Fig. 2). No dyskeratotic cells were observed. In the upper dermis of the central part of the lesion, a massive cell in®ltrate composed mostly of plasma cells with some lymphocytes was seen. Immunohistochemically, the skin specimen revealed IgG deposits in the intercellular space (ICS) of the entire epidermis and, similarly, C3 in the lower epidermis. Indirect immuno ̄uorescence studies gave an evidence of circulating anti-ICS antibodies of IgG class (616). Immunoblot analysis (1) indicated that the serum reacted with the 130 kDa protein, PV antigen (Fig. 3). The skin lesion healed after surgical removal and no recurrence was observed for 24 months. The erosive lesion of the lip margin lasted for 6 months, despite application of corticosteroid ointment. After 10 days' application of gentamycin ointment, it was epithelized. The erosion reappeared after 5 months. The lip lesion was excised 3 months later and histologically and immunohistochemically revealed almost the same ®ndings, except hyperkeratosis, as in the skin. Since then, it has not recurred at least for 18 months.